title: Functional dissection of transmembrane domains of human TAP-like (ABCB9).
abstract: An ABC transporter, TAP-Like (TAPL), was dissected into its amino-terminal transmembrane domain and the following core domain. When these domains were transiently expressed as tagged proteins with a His6- or Myc-epitope tag, the amino-terminal ones (Met(1)-Lys(182)) could not associate with each other, or with the full-length transporter (Met(1)-Ala(766)). However, both the core domain (Arg(141)-Ala(766)) and full-length protein mutually interacted. The amino-terminal domain (Met(1)-Arg(141)) as well as the full-length transporter fused with fluorescent protein GFP was sorted to lysosomal membranes upon their stable expression, as visualized by means of fluorescent microscopy, while the core domain (Arg(141)-Ala(766)) was broadly distributed in the intra-cellular membranes. These results suggest that the sorting signal for lysosomes is present within the amino-terminal transmembrane domain (Met(1)-Arg(141)) of the TAPL molecule.
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Kamakura
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Fujimoto
authors.forename: Yu
authors.initials: Y
authors.lastname: Motohashi
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Ohashi
authors.forename: Ayako
authors.initials: A
authors.lastname: Ohashi-Kobayashi
authors.forename: Masatomo
authors.initials: M
authors.lastname: Maeda
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008247:Lysosomes / Q000378:metabolism; D021382:Protein Sorting Signals / Q000235:genetics; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary / Q000235:genetics
chemical_list: C412573:ABCB9 protein, human; D018528:ATP-Binding Cassette Transporters; D021382:Protein Sorting Signals; D049452:Green Fluorescent Proteins